Universität
UniversitätStuttgart
Stuttgart
INSTITUT FÜR
INSTITUT FÜR
NACHRICHTENVERMITTLUNG KOMMUNIKATIONSNETZE
UND DATENVERARBEITUNG UND RECHNERSYSTEME
Prof. Dr.-Ing. Dr. h. c. mult. P. J. Kühn Prof. Dr.-Ing. Dr. h. c. mult. P. J. Kühn
ICT Developments: Technological, Architectural,
Traffic Engineering and QoS Challenges
Paul J. Kühn
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Pfaffenwaldring 47, 70569 Stuttgart
kuehn@ikr.uni-stuttgart.de
Regional Seminar on Fixed Mobile Convergence and new network architectures
Tunis, November 21-24, 2005
Outline
1. Development of Network Technologies and Services
1. Digital Telecommunication Networks
2. Packet Networks
3. Mobile Communication Networks
4. Services and Applications
2. Network Convergence
1. Horizontal and Vertical Integration
2. Towards IP-Based Networks
3. Ambient, Ubiquitous and Nomadic Communications
3. Technical Challenges of NGN
1. Architectures and Platforms
2. Component Technologies
3. Quality of Service and Traffic Engineering
4. Network Management and Self-Organization
5. Security
4. Conclusions
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Development of Network Technologies
EM Electromechanical Technology
TDM Time Division Multiplex
ATM Asynchronous Transfer Mode
ON Optical Networks
2G 2nd Generation MC Networks
2.5 G 2.5nd Generation MC Netw.
3 G 3rd Generation MC Networks
> 3 G Beyond 3rd Generation MC Netw
Telecommunication
Networks
Digital, Cellular
MC Networks
X.25 ITU Packet Standard
IPv4 Internet Protocol Version 4
IPv6 Internet Protocol Version 6
LAN Local Area Networks
Packet
Networks
MAN Metropolitan Area Networks
NGI
WLAN Wireless LAN
Time
1960
1970
1980
1990
2000
2010
2020
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Telecommunication Networks
Mobile Network
Fixed Network
Telefax
MSC
Telephon
BS
Switching
Node
Mobile
Stations
HLR/VLR
SCP
SDP
• 1200 Million Subscribers (Fixed Network)
Annual Growth 10%
• 1400 Million Subscribers (Mobile Networks)
Annual Growth 50%
• Intelligent Network Services (IN)
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Computer Communication Networks
PC
Server
Telephone
Network
Internet
POP
R
R
WS
R
R
R
Intranet
• Probably more than 100 000 Subnetworks
and more than 700 Million Users
• Services: Electronic Mail, Database Access,
File Transfer, Internet Telephony,
Multimedia Communication, World Wide Web,
Peer-to-Peer
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Technological Developments
BS
Ground
Station
ADM
GY
MSC
NG Internet
ATM
Fibre Optic Channels
Photonic
Switch
OCC
Institute of Communication Networks and Computer Engineering
Photonic
Backbone
Mobiles
Fixed
Access Networks
Mobile
Core Networks
Low Earth Orbit
Satellites
University of Stuttgart
Development of User Numbers
Source: ITU News 2/2002
Mobile Users
Million Users
1500
Fixed Telephone
Network
Subscribers
Internet Users
1000
500
0
1990
1995
2000
Institute of Communication Networks and Computer Engineering
2005
University of Stuttgart
Application Areas and Communication Services
Telecommunication
Telephonie Multimedia-Mail
Telefax
Videoconference
Tele-Education
E-Mail
Telecooperation
Home Working
Computer
Communication
Remote Login
Focused
Advertizing
Video-onDemand
Advanced
Pay-per-view
Data Communication Distributed
Information
Electronic Newspaper
Stored Multimedia
Access
Data Base Access
Context
Location Based
Services
Context
Awareness
World Wide Web
Sensor
Applications
Peer-to-Peer
Application
Tele-XYZ
e-Business
Portals
Business Applications
Video Games
Entertainment
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Peer-to-Peer File Sharing
Server + Client
(Servent)
Overlay
Network
Request
(Query)
Query
Hits
Underlying
unreliable
Internet
(TCP/IP)
Autonomous
System
Autonomous
System
Autonomous
System
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Application Scenario
Navigation Support
Satellite
Sensor
Radio
Access
Network 1
Fixed Network
Radio
Access
Network 2
MT
...
Federation
Server
Data Base
Systems
MT
Congestion
ahead
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Application Scenario
Trust Center
Electronic Ticket
Bank
Railway
Booking
Centre
(4)
(3)
(2)
Smart
Card
BSS
MSC
PDA +
Mobile
Phone
Conductor
(1)
Smart
Card
HLR/VLR
Railway Customer
PDA
(5)
ICE
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Outline
1. Development of Network Technologies and Services
1. Digital Telecommunication Networks
2. Packet Networks
3. Mobile Communication Networks
4. Services and Applications
2. Network Convergence
1. Horizontal and Vertical Integration
2. Towards IP-Based Networks
3. Ambient, Ubiquitous and Nomadic Communications
3. Technical Challenges of NGN
1. Architectures and Platforms
2. Component Technologies
3. Quality of Service and Traffic Engineering
4. Network Management and Self-Organization
5. Security
4. Conclusions
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Network Convergence
User Terminal A
User Terminal B
Access
Media
GY
Network 1
ISDN
Network 2
GY
Access
SIP
Network 3
GY
Network 4
WLAN
GPRS
• Users may have access to networks of different technologies
• Communication across networks of identical / different technologies
• "Always best connected"
• Wide spectrum of services
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Horizontal and Vertical Integration
Statements: Existing networks: ISDN, Mobile Networks, Internet, ...
Future trend: IP-based networks
Questions: Transition from existing networks to future IP-based networks
Architecture, protocols, migration
SIP
Fixed Networks
4
Op. #3
Internet
SIP
Horizontal
Integration
Fixed Networks
1
Op. #1
Conventional
coupling
Fixed Networks
Media
Gateway
2
Op. #2
ISDN
Horizontal
Integration
ISDN
Vertical
Integration
Institute of Communication Networks and Computer Engineering
Fixed Networks
3
Op. #2
SIP
University of Stuttgart
Development Scenario
Service and Technology Convergence
Services
E-mail
File Transfer
VoIP
Web
Audio
Video
Multimedia
Transport
E-Commerce
Games
IP
Technologies
ISDN ATM GSM
B-ISDN
UMTS
LAN MAN WLAN
FR
SDH WDM FTTX HFC
Institute of Communication Networks and Computer Engineering
PC
University of Stuttgart
Ambient, Ubiquitous and Nomadic Communications
Ambient Communications
➥ Location and Context Awareness
Examples:
Location Based Services
Context Aware Services
Ubiquitous Communications
➥ Distribution of Computer and Communication Functions in many devices
("smart its")
Examples:
Body (Personal) Area Networks
Sensor / Actor Networks
Nomadic Communications
➥ Communication from any place including use of local / distant facilities
Extension of the Mobile Communications Paradigm
Institute of Communication Networks and Computer Engineering
University of Stuttgart
New Mobile Services
Communication Services ➔ Emerging Topics
•
•
•
information services
➥
location/context aware
services, navigation services, ...)
classical information services
➥ MMS, e-mail, ...
stream-oriented services
➥ speech and video telephony, ...
•
•
•
new services
➥ minimalistic user interface
new requirements to the networks
➥ mobility manangement/support
➥ resource reservations
➥ support for hundreds of niche applications
business models
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Communication Scenarios
Heterogeneous Access Networks
•
wireless network technologies are designed for special environments
➥ e. g. indoor/outdoor, slow/fast users, low battery consumption, ...
outdoor
UMTS / EGPRS
Info-Station
in-house
Wireless LAN
Wireless LAN
Quelle: U. Kubach (IPVR/AS),
Universität Stuttgart, 2001
•
•
•
change of paradigm: from anytime-anywhere to sometime-somewhere
critical: network transitions in vertical direction
users always want to use the best available network
- but without manual interactions
➥ research topic: Always Best Connected (ABC)
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Challenge: Adaptation of Networks and Applications
• inter-technology mobility support
network availabilities
• abstraction of networks and
technologies
user path
GPRS/UMTS
y
HIPERLAN
WLAN
x
wire-based
access
network
nets
WLAN
Internet
core
Bluetooth
GPRS/UMTS
Bluetooth
t
wireless
access
network
user requirements
(user view)
wireless
access
network
Nutzerbewegung
LBS use
E-Mail use
LS update
service
LS update
LBS
• fair and adequate resource
sharing
• control of communication costs
E-Mail
t
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Nexus – An Open Platform for
Location-/Context-Aware Applications
Project Aims (Interdisciplinary)
• platform for the support of context-aware services
➥ open system platform
• "world model" for context aware systems
Quelle: IPVR/VS, Universität Stuttgart, 1999
• technology assessment
➥ security and privacy aspects, social acceptance, ...
• applications
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Outline
1. Development of Network Technologies and Services
1. Digital Telecommunication Networks
2. Packet Networks
3. Mobile Communication Networks
4. Services and Applications
2. Network Convergence
1. Horizontal and Vertical Integration
2. Towards IP-Based Networks
3. Ambient, Ubiquitous and Nomadic Communications
3. Technical Challenges of NGN
1. Architectures and Platforms
2. Component Technologies
3. Quality of Service and Traffic Engineering
4. Network Management and Self-Organization
5. Security
4. Conclusions
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Technical Challenges of NGN
Topics
Examples
1. Architectures and Platforms
• Control of Dynamic Transport
Networks
• Optical Burst Switching
• NGN Service Platforms
2. Quality of Services and Traffic
Engineering
• Traditional Solutions
3. Communication & Security
• Architectures and Protocols
• QoS in the Internet
• Mobility
• Security and Privacy
Institute of Communication Networks and Computer Engineering
University of Stuttgart
ASTN Functionality
• Provisioned/hard permanent connection (PC)
- controlled by management system
- long provisioning times
management plane
service request
(fax, web, …)
company
branch
provisioning
request
transport plane
Institute of Communication Networks and Computer Engineering
service
technician
company
headquarters
University of Stuttgart
ASTN Functionality
• Switched connection (SC)
- uses control plane with user-network-interface (UNI) and
internal/external network-network-interface (I-NNI/E-NNI)
- dynamic information exchange
• Soft permanent connection: SC only within network, no UNI
I-NNI
control plane
E-NNI
UNI
UNI
company
branch
company
headquarters
transport plane
domain/operator A
domain/operator B
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Multilayer Networks - Architecture
EXC
WL granularity
SDH layer
optical layer
OXC
• Circuit switched transport network
• Evolutionary extension of current core networks
• Optimal combination of
- optical transport
- electronic aggregation and traffic engineering
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Optical Burst Switching
..
.
..
.
..
.
edge node
core node
OBS network
control-channel
OBS link
data-channels
• Burst assembly in edge node,
mostly variable length
• Fast optical switch [Vortrag HHI]
• Separation of control and data
• WDM-based transmissionHHI]
• Separation of control and data
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Contention Resolution in OBS
• Burst loss possible due to bufferless statistical multiplexing
• Application of OBS in high-speed metro/core networks
➥ lost data has to be retransmitted on end-to-end basis not locally
➥ very low burst loss probability required (e.g., 10-6)
➥ Need for highly effective contention resolution
• Wavelength domain
wavelength conversion
- very effective as all WDM channels shared among all bursts
- but: low burst loss probabilities only for ≥ 100 λs
➥ additional schemes necessary
• Time domain
fiber delay lines (FDLs)
• Space domain
deflection/alternative routing
➥ Optimized combination of these schemes
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Contention Resolution in OBS
input
fibers
1
output
fibers
1
2
2
N
N
shared
converter
pool
FDL
buffer
matrix
1
Selection strategies for
converter and FDLs
minDelay
minConv
FDL 2
FDL 1
no FDL
NC
λ0 λ1 λ2
λ0 λ1 λ2
1
NF
• Potential for resource/performance optimization in OBS node
• Different selection strategies for converters and FDLs
- minDelay minimizes delay at cost of higher converter usage
- minConv minimizes converter usage at cost of higher delays
Institute of Communication Networks and Computer Engineering
University of Stuttgart
NGN Service Platforms
Voice, Video, Streaming
Application Platform
Business Applications
e-XYZ, m-XYZ, ...
Open Interfaces
Web Services Middleware
...
Service Platform
Roaming
SIP
AAA
...
Open Interfaces
ISDN,
DSL
GSM
GPRS
UMTS
WLAN
...
DVB
WiMax
Institute of Communication Networks and Computer Engineering
Access &
Core Transport
University of Stuttgart
Technical Challenges of NGN
Topics
Examples
1. Architectures and Platforms
• Control of Dynamic Transport
Networks
• Optical Burst Switching
• NGN Service Platforms
2. Quality of Services and Traffic
Engineering
• Traditional Solutions
3. Communication & Security
• Architectures and Protocols
• QoS in the Internet
• Mobility
• Security and Privacy
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Traditional Solutions
Example 1: Telecommunication Services
Connection: Reservation of Bandwidth
Network
B
A
Admission Control
Circuit Switching
Traditional Solution is not feasible for many new applications due to:
• Variable bitrate sources (burst traffic)
• Overhead for connection management (delay, state management, ...)
• Integration of many services with quite different characteristics
• Inflexibility with respect to adaptation to application requirements
• Cost
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Traditional Solutions
Example 2: Internet
Network
Datagram
routing
Server
Client
"Best Effort Service": No admission control
No resource reservation
Unpredictable delays and losses
BES is not feasible for many new applications due to:
• No guarantees on QoS
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Internet Routing
RIP
BGP
RIP
Domain 2
(RIP)
Domain 1
(RIP)
BGP
Domain Router
RIP
OSPF
BGP
Edge Router
Routing Information Protocol
Open Shortest Path First
Border Gateway Protocol
Institute of Communication Networks and Computer Engineering
OSPF
Domain 3
(OSPF)
University of Stuttgart
QoS Management in the Internet
Traffic Classes in the IntServ-Model
• Guaranteed Service
(similar to CBR and rt-VBR)
• Controlled Load Service
(similar to nrt-VBR)
• Best Effort Service
(similar to UBR)
Use of RSVP
Traffic Classes in the DiffServ-Model
• Expedited Forwarding
(Premium Service)
• Assured Forwarding with different Priorities
Hop-by-Hop Control
Institute of Communication Networks and Computer Engineering
University of Stuttgart
IntServ-Model
Source
Router
Router
Destination
PATH Messages
RESV Messages
Soft-State
Soft-State
Periodic Updates
of Soft-State
Reservations
Flow Description by
Flow Specifications (FlowSpec)
Service Class
Reserve Specification (RSpec)
Traffic Specification (TSpec)
Filter Specification (FilterSpec)
Institute of Communication Networks and Computer Engineering
University of Stuttgart
DiffServ Model
Access
Router
Border
Router
Border
Router
Access
Router
Backbone
Internet of ISP
Subnetwork
A
Subnetwork
A
Negotiation of max. Bitrate between User and ISP for Aggregated Traffic Volumes
Classification of Traffic Class by Access Routers
Premium Service:
Separate Queues and Prioritized Transport provide
virtual leased Line Service
Policing Function by Border Router
Assured Service:
Use of Priority to provide QoS for short Bursts
Policing Function and Packet Dropping by Border Router
Appropriate Dimensioning of Transmission Resources by ISP
Per Hop Behaviour (PHB) Routing, Marking of IP Packets within DS-Field
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Tag Switching
R
Tag Distribution
Edge
Router
Edge
Router
S
R
Packet Flow
S
• Detection of flows
• Assignment of flow labels
• Fast switching along pathes
Institute of Communication Networks and Computer Engineering
State-based switching
University of Stuttgart
Challenges of NG Internet with Respect to QOS
• Tremendous increase in bandwidth demand in mobile and fixed networks for new applications
Ahead: Japan and Rep. of Korea (70/60 % mobile Internet users;
US/Europe < 10%)
Asia-Pacific Region leading in broadband penetration
• Rapid decrease of internat. bandw. pricing from 111 TUSD (1998) to
10 TUSD (2002) for US-Japan 1Mbps link per year
• NG Internet Technology and broadband access
• Fast routing algorithms
• Convergence of Internet and Mobility
• Adaptive traffic control (e.g., for Peer-to-Peer applications)
• Negotiable QoS Levels and QoS guarantees
• Accounting and charging for highly variable bitrate services
• Ubiquitous computing and ad hoc communication networks
• Adaptation of source coding and network traffic control
• QoS across multiple layers and heterogeneous network technologies
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Technical Challenges of NGN
Topics
Examples
1. Architectures and Platforms
• Control of Dynamic Transport
Networks
• Optical Burst Switching
• NGN Service Platforms
2. Quality of Services and Traffic
Engineering
• Traditional Solutions
3. Communication & Security
• Architectures and Protocols
• QoS in the Internet
• Mobility
• Security and Privacy
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Research Topics - Communication & Security
Architectures & Protocols
• Unified Communication based on IPv6
• Communication across different Networks
• Mobility Management based on Mobile IP Concepts
• Dynamic Address Management
• Horizontal and Vertical Handover
• Integration of Ad Hoc Networks (infrastructureless)
• Middleware Concepts
Abstraction from Underlying Network Infrastructures
• Design & Implementation
• Standardization
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Research Topics - Communication & Security
Mobility
• Modelling of Mobility of Users and Data
• Modelling of (Communication) Traffic
-spatial and temporal
• Disconnected Operation (information Caching and Fuelling)
• Predictive Information Provision (Hoarding)
• Simulation Methods for Mobility
• Performance
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Research Topics - Security & Privacy
Example
HLR/VLR
BC
MSC
• Tracking of Location May Cause Severe Privacy Problems
• Similar Problems Arise from Recording of User Activities
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Research Topics - Security & Privacy
• Protection Against Concatenation between
Location Data and User Identity
• Methods:
• Pseudonymization
• Authentication
• Multilateral Security concepts:
Negotiation of Protection Aims and Strengths
• Accountability and Non-Repudiation
• Integrity
• Security Protocol Design
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Conclusion (1): General Observations
• Change of Paradigms in the Communication Sector
- heterogeneous network technologies, broad spectrum of applications
- trend directs to IP-based network and transport protocols
- technology push and market pull
• Success Factors
- time to market
- open platforms
- user acceptance
• Design Processes
- limited development periods
- specialization and limitation to core competences ("make or buy?")
- design automation, design platforms and tools
• Standardization and Quality
- proprietary solutions vs. open platforms
- need for standardization
- product quality and quality of service
Institute of Communication Networks and Computer Engineering
University of Stuttgart
Conclusion (2): Research Areas
• Integration of the various Network Technologies
- fixed, mobile and ad hoc networks
- internet and photonic technologies
- support of autoconfiguration and manageability
• Platforms
- advanced middleware concepts
- service creation support
- application programming interfaces
• New Application Paradigms
- location and context based services
- nomadic communications and ubiquitious computing
- overlay networks
• New Business Models
- micropayment
- quality of service
- scalable security
Institute of Communication Networks and Computer Engineering
University of Stuttgart